Multiple Compute Units (Asymmetrical) XRT (XRT Native API’s)¶
This is simple example of vector addition to demonstrate how to connect each compute unit to different banks and how to use these compute units in host applications using xrt native api’s.
KEY CONCEPTS: Multiple compute units, Task Level Parallelism
This example demonstrates how to use multiple compute units of same kernels which are asymmetrical i.e. connected to different memory banks.
Kernel can be connected to different banks using vadd.cfg file as below:
[connectivity]
nk=vadd:4:vadd_1.vadd_2.vadd_3.vadd_4
sp=vadd_1.in1:DDR[0]
sp=vadd_1.in2:DDR[0]
sp=vadd_1.out:DDR[0]
sp=vadd_2.in1:DDR[1]
sp=vadd_2.in2:DDR[1]
sp=vadd_2.out:DDR[1]
sp=vadd_3.in1:PLRAM[0]
sp=vadd_3.in2:PLRAM[0]
sp=vadd_3.out:PLRAM[0]
sp=vadd_4.in1:PLRAM[1]
sp=vadd_4.in2:PLRAM[1]
sp=vadd_4.out:PLRAM[1]
Some of the vadd compute units are connected to DDR banks and some are
connected to PLRAMs. nk
option can be used to specify how many
compute unit are needed for vadd
kernel. It also allows to give
names of user choice. sp
option can be used to provide connection of
compute units to target memory (DDR, PLRAM).
vadd.cfg
file should be included in v++ command line as below:
--config vadd.cfg
As each compute unit are connected to diferrent DDR/PLRAM, so host program has to create kernel object specific to compute unit as below:
xrt::kernel cu0_krnl = xrt::kernel(device, uuid, "vadd:{vadd_1}");
The kernel object which is created above is very specific to vadd_1
compute unit. Using this Kernel Object, host can directly access to this
fix compute unit.
EXCLUDED PLATFORMS:
Alveo U25 SmartNIC
Alveo U30
Alveo U50
Alveo U55
All Versal Platforms, i.e vck190 etc
Samsung SmartSSD Computation Storage Drive
Samsung U.2 SmartSSD
All Embedded Zynq Platforms, i.e zc702, zcu102 etc
X3 Compute Shell
All NoDMA Platforms, i.e u50 nodma etc
DESIGN FILES¶
Application code is located in the src directory. Accelerator binary files will be compiled to the xclbin directory. The xclbin directory is required by the Makefile and its contents will be filled during compilation. A listing of all the files in this example is shown below
src/host.cpp
src/vadd.cpp
Access these files in the github repo by clicking here.
COMMAND LINE ARGUMENTS¶
Once the environment has been configured, the application can be executed by
./multiple_cus_asymmetrical_xrt -x <vadd XCLBIN>